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<h1><a name="SECTION0024100000000000000000">
22.1 <tt class="module">cmd</tt> --
         Support for line-oriented command interpreters</a>
</h1>

<p>
<a name="module-cmd"></a>

<p>
The <tt class="class">Cmd</tt> class provides a simple framework for writing
line-oriented command interpreters.  These are often useful for
test harnesses, administrative tools, and prototypes that will
later be wrapped in a more sophisticated interface.

<p>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline">
  <td><nobr><b><span class="typelabel">class</span>&nbsp;<tt id='l2h-4891' xml:id='l2h-4891' class="class">Cmd</tt></b>(</nobr></td>
  <td><var></var><big>[</big><var>completekey</var><big>[</big><var>,
                       stdin</var><big>[</big><var>, stdout</var><big>]</big><var></var><big>]</big><var></var><big>]</big><var></var>)</td></tr></table></dt>
<dd>
A <tt class="class">Cmd</tt> instance or subclass instance is a line-oriented
interpreter framework.  There is no good reason to instantiate
<tt class="class">Cmd</tt> itself; rather, it's useful as a superclass of an
interpreter class you define yourself in order to inherit
<tt class="class">Cmd</tt>'s methods and encapsulate action methods.

<p>
The optional argument <var>completekey</var> is the <tt class="module"><a href="module-readline.html">readline</a></tt> name
of a completion key; it defaults to <kbd>Tab</kbd>. If <var>completekey</var> is
not <tt class="constant">None</tt> and <tt class="module"><a href="module-readline.html">readline</a></tt> is available, command completion
is done automatically.

<p>
The optional arguments <var>stdin</var> and <var>stdout</var> specify the 
input and output file objects that the Cmd instance or subclass 
instance will use for input and output. If not specified, they
will default to <var>sys.stdin</var> and <var>sys.stdout</var>.

<p>

<span class="versionnote">Changed in version 2.3:
The <var>stdin</var> and <var>stdout</var> parameters were added.</span>

</dl>

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<span class="release-info">Release 2.5.1, documentation updated on 18th April, 2007.</span>
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